Sewing machine



Nov..23, 1943. H. HER'II'ZBERGER v SEWING MACHINE Filed Dec. 8, 1941INVENTOR fl'crm'arz HZWZk/yer BY 7 W ATTORNEY Pa se Nov. 23, 1943 asnwrno monlnsfl 3 it f Herman e tage; New York, N. r. V

= it Application Dcemlier8f1941', Serial 1 "InGonnany Jul y 3, 1941This-invention relates to sewieg aehmes, and

more particularly to a novel attetnmefitr r sew:

i n s r sub o i ent Jd sse the needle from pthe; worlclvwhen the-mac ineis stopped l The device offthefin ve articularly defsigned for use in'conne'etion With sewing-' ma chines whichimake about 3990 stitchesperfr ninie an or u l sewi a ii n sb t i type ,are d riven by fanlelectric 'ro'otorfand are;

used' in the textile-industry.

"Frequently numberffoffparallel rows. "of stitches must besewedonthe.sameigoods; Every timea row has'been finished the sewingmachine must be stopped." "Then" the worker-mist diseng gagejtheneedlefromfthe work before, he can start with the next row ofistitohes.Crenerally this is-Idone by rotating the balance wheel of I wherein;

beerr stopped, 1 V i Ajfurther object of the invention is to providefrom 'the 'work after the sewin'g' machine has an apparatus whichffirstswitches off the electric drive motor'of thesew ing machine andfth'enautomatically disengages the needle from i the 1 rhe eanurur ner objects'of'the invention {will become more apparent 'fwhen the descriptionproceeds taken Fig. 1 is 'a schematicside View taken from th I left-handside of a sewingm 1:

the sewingmachine, and to this end the'worker must removeonehandfrornthe work. The inventor'has found that'if the, time requiredfor sewing an open lining is for instance54 seconds then 16 seconds arerequired for disengaging the needle from the work. v s V In accordancewith the invention this drawbackis removed. The machine of the invenjtion comprises a device for automatically disengagingthe needle from'thework after the' sewing machine has been stopped or nearly: brought to astandstilL; Preferably, the device of the invention is actuated by thfoot or the {Fig 2 isa schematic sideyiew taken fromthe right ha'nd'side of asewing machine trating the device of l the invention. i

Referring to thefdrawing'; thelsewing machine comprises amain driveshaftdirbearing aorank ll connectldjwith connecting 'rod l2 driving' inturn' c'rosshead i3. -"Crosshead i3- is guided in bearing ll' and bearsneedle-l5', "removably se cured by screw I6. The'work I1 is supported ontable I 8. wheel 20 driven'by electric motor 2| by means of belt 22. I

It will 'be evident that whencrank ll is in V any position within theangl indicated. at a,

needle l5 will bedisengaged from work I'L *Only knee of. the operator sothat he can use both hands for holding and moving the work.

' Preferably the device 0f the invention. is connected with a switch forswitching on the drive' motor of the sewing machine. By actuating forinstance a foot pedal the switch'isfirst actuated;

for disengaging the needle'from the :work};

and then the device of the invention is' released, 7

. In a preferred embodiment of the invention the balance wheel of thesewing machine. which is secured to the main drire-sh'aft has 'aimembersdepending therefrom which may .for .instancebe. 'a stud. This stud isadapted to cooperate with a member such as a plate which, is normallybelow the balance whee]. When the-drive motor 7 of the sewing machine isdisengaged-this;plate is lifted to'engage the stud Thus the balancewheel is rotated until. the needle is disengaged,

from the work.

7 It is accordingly anobl'ect of the invention to rovide anovelattachment for sewing vmachines.

V Anotherobject of the invention is to provide. a device forautomatically disengaging the needle when crank H is in aposition belowangle a,

needle l5 pierces work ll. In order to disengage the needle from thework it is therefore only' necessary to bring crank within angle a.

ll into any position To this end balance wheel 23 secured'to main shaftHi is provided with stud 24. Preferably, 7' stud 24 is arranged so thatit is aligned with" crankll. Stud is adapted tocooperate with plate 25which is urged'f downwardly by springs 26, 26. Springs 28, 25am securedto base 21 supported by a frame work 28. 1 Plate 25.has a dependingrod3!].guided in bearing 3|. Rod 30 is adapted to be lifted by cam32secured to shaft 33. Lever 34 issecurd to shaft 33 and base; Ipin-engaging slot '35 in lever 36. 1 The lower end g of lever 36 issecured to foot pedal Slat 38, Pedal 3! has its fulcrumatfl where it issecured to ,frame work ,28 Spring 4| urges pedal 31 upwards into itsdotted position 31a. Switch lever 142 has a'lost-motionconnection withrodfifiiand actuates switch 43; current is conducted to the switch bywires 44; Switch lever iZ carried at 'its one end a contact segment 53.The current i is conducted through wires. 7

connected with wires 5i and 52 leading to'terminals 50 andf55.

These wires are in connection with the drawing;

and illust Driveshaft I 0. has secured thereto:

" The operation of my novel device will now be evident. Normally footpedal 31 is in the dotted position 31a. Cam 32 is in its dotted position32a and is not in engagement with rod30. Hence springs 26 are free topull plate 25 against bear:

'ing 3| Motor 2| is energi'zedwhen the switch lever is in its positionindicated at 42a.

When it is desired to stop the sewing machine and to disengage theneedle, the. operator) pressesdowniootjbedal 3'la which now moves intothe full-line position 31. This causes a downward movement of switchlever 42a for switching off v.

motor 2|. Due to the lost-motion connection between rod 36 and crank 34the latter does not start to move until motor 2| has .beenswitched off.Further downward movement of pedal 31; causes rotation of cam 32a'intoits full line posij Now plate i 25 brings stud 24 intothe position shownin tion.32 which causes lifting of rod 30.

' tion without-departing from the broader-spirit andscopethereof,assetforth-in the following:

claimsiy I claim: v

'1. In.a sewing machine. having a main shaft,

an electric motor for driving said shaft, a,bal-- ance wheel-onsaidshaft, and a needle-operatively connected with a said shaft andreciprocated thereby, a switch forsaid motor,- a-device forautomaticallydisengaging said needle includingwanv element extendingfrom -said-lbalance wheel; a plate normally arranged belowsaid ele-=mentga cam arrangedto lift said-plate-on rotation'thereof, a foot pedaloperatively connected with said cam by a lost-motion connection and] v Iconnected with said switch for actuation thereof whereby when said pedalis movedv said switch is switched off and said plate is engaged withsaid element,

,2. In a sewing machine having a main shaft, an electric motor fordriving said shaft, a switch 1 for said motor, a balance wheel on saidshaft,

and a needlepperatively, connected-with said, shaft andreciprocatedthereby, a device for automatically disengaging said-needleincluding a stud on said balance wheel, aid stud having 'a predeterminedposition, a plate normally arranged' below said stud, a spring urgingsaid plate away from said stud, a cam arranged to lift 1 said plate onrotation thereof, a foot pedal, a rod connectedwith-said foot pedal andhaving a lost-motion connection with said cam, said rod being connectedwith said switch for actuation I thereof, whereby actuation of saidpedal causes first switching oif of said switchand thereafter rotationof said cam. .7 I 1 -3. Ina sewing machine having a main shaft,

an electric motor for driving said shaft, a switch for said motor, abalance wheel on said shaft,

and a needle operatively connected. with said shaft and reciprocatedvthereby, a device iori automatically disengaging said needle including'astud 'on rsaidbalance wheel having a prede termined position, a platenormally arrangedbelow said stud and having a projection in its center,a spring for-urging said plate-away from 7 said stud, a cam arranged tolift said plate on' rotation thereof, a foot pedal operatively COD-rnected with said cam by a lost-motion connection and connected with saidswitch for actuation thereof whereby movement of said pedal. causes.

switching off of said switch and lifting of-. said plate into engagementwith said-stud. I

' HERMA HERTZBERGERQ 7

